| Quadrangle map, 1:250,000-scale | SO |
|---|---|
| Quadrangle map, 1:63,360-scale | C-5 |
| Latitude | 64.648 |
| Longitude | -164.293 |
| Nearby scientific data | Find additional scientific data near this location |
| Location and accuracy | This locality is on the south side of Big Hurrah Creek, at an elevation of about 250 feet, and 0.6 miles southeast of its mouth. It is locality 17 of Cobb (1972, MF 445; 1978, OF 78-181). |
Geologic descriptionA lens of stibnite, 12 to 18 inches thick, occurs within a 4-foot-thick quartz vein in a brecciated zone containing disseminated pyrite; the lens strikes northeast and dips northwest. Stibnite occurs in bladed crystals 1 to 3 inches long and as finely disseminated material. Collier and others (1908) report only traces of Au and Ag. Five tons of ore with 63.7% antimony, no lead or zinc, and only traces of arsenic, were mined and 3 tons were shipped in 1915-16 (Mertie, 1918). The host rock is black, very fine-grained, graphitic schist. Bedrock here is part of a lower Paleozoic metasedimentary assemblage (Sainsbury and others, 1972, OFR 511; Till and others, 1986). This deposit may be the same age as some gold-quartz veins of southern Seward Peninsula. The southern Seward Peninsula lode gold deposits formed as a result of mid-Cretaceous metamorphism (Apodoca, 1994; Ford, 1993, Ford and Snee, 1996; Goldfarb and others, 1997) that accompanied regional extension (Miller and Hudson, 1991) and crustal melting (Hudson, 1994). This higher temperature metamorphism was superimposed on high pressure/low temperature metamorphic rocks of the region. | |
| Geologic map unit | (-164.295605198151, 64.6472574111404) |
|---|---|
| Mineral deposit model | Quartz-stibnite vein in graphitic schist; simple Sb deposits (Cox and Singer, 1986; model 27a). |
| Mineral deposit model number | 27d |
| Age of mineralization | Cretaceous? |
| Alteration of deposit | Silicification. |
| Workings or exploration | A 12-foot shaft and several trenches exposed the vein in early workings (Cathcart, 1922). |
|---|---|
| Indication of production | Yes; small |
| Production notes | Five tons of ore with 63.7% antimony, no lead or zinc , and only traces of arsenic, were mined and 3 tons were shipped in 1915-16 (Mertie, 1918). |
| MRDS Number | A012592 |
|---|---|
ReferencesApodoca, L.E., 1994, Genesis of lode gold deposits of the Rock Creek area, Nome mining district, Seward Peninsula, Alaska: Boulder, Colorado, University of Colorado, Ph.D. dissertation, 208 p.
Ford, R.C., 1993, Geology, geochemistry, and age of gold lodes at Bluff and Mt. Distin, Seward Peninsula, Alaska: Golden, Colorado School of Mines, Ph.D. dissertation, 302 p.
Ford, R.C., and Snee, L.W., 1996, 40Ar/39Ar thermochronology of white mica from the Nome district, Alaska--The first ages of lode sources to placer gold deposits in the Seward Peninsula: Economic Geology, v. 91, p. 213-220.
Goldfarb, R.J., Miller, L.D., Leach, D.L., and Snee, L.W, 1997, Gold deposits in metamorphic rocks in Alaska, in Goldfarb, R.J., and Miller, L.D., eds., Mineral Deposits of Alaska: Economic Geology Monograph 9, p. 151-190.
Hudson, T.L., 1994, Crustal melting events in Alaska, in Plafker, G., and Berg, H. C., eds., The Geology of Alaska: Geological Society of America, DNAG, The Geology of North America, Vol. G-1, p. 657-670.
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| Reporters | Travis L. Hudson (Applied Geology) |
| Last report date | 8/19/1999 |